AUBURN, Alabama -- Auburn quarterback Nick Marshall headed to the locker room early in the second quarter against Florida Atlantic with an injury that appeared to affect his throwing shoulder.

Marshall returned to Auburn's sidelines late in the second quarter, out of uniform and wearing a gray pullover, although he was still wearing his game pants.

Auburn quarterback Nick Marshall (14) on the sidelines after injury during the second quarter Saturday, Oct. 26, 2013, at Jordan-Hare Stadium in Auburn, Ala. (Julie Bennett/jbennett@al.com)

Marshall, who had 73 yards and a touchdown on six carries and completed one pass for 10 yards, was injured on a sack by Florida Atlantic's Robinson Eugene.

"The only update is that he's not going to play in the second half,' Auburn coach Gus Malzahn told the radio during halftime.

Auburn announced in the press box in the third quarter that Marshall injured his shoulder and would be held out of the second half for precautionary measures.

After the play, Marshall stayed down on the field and was attended to by trainers before getting up and leaving the field, holding his right arm gingerly.

Trainers could be seen working on Marshall's right shoulder -- pushing up underneath his shoulder pad -- before taking the quarterback to the locker room.

Auburn's radio broadcasters offered a short update on Marshall after he went to the locker room.

While trainers were working on Marshall, backup Jeremy Johnson threw a 36-yard touchdown pass to Sammie Coates, and Marshall raised his left arm in celebration, but it was clear his right shoulder was affected.

On his way off the field, Marshall high-fived several teammates, but he always used the left arm.

Trainers initially looked at Marshall's right shoulder near the eight-minute mark, shortly before he scored on a 10-yard touchdown run to put the Tigers up 21-0.

"Nick is dinged up," Auburn radio broadcaster Rod Bramblett said. "Should be OK, we understand, but it looks like it's Jeremy's game."